Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
  • B05D7/06—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to wood
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
  • C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
  • C09D175/04—Polyurethanes
  • C09D175/14—Polyurethanes having carbon-to-carbon unsaturated bonds
  • C09D175/16—Polyurethanes having carbon-to-carbon unsaturated bonds having terminal carbon-to-carbon unsaturated bonds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
  • B05D7/06—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to wood
  • B05D7/08—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to wood using synthetic lacquers or varnishes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
  • B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
  • B27K3/00—Impregnating wood, e.g. impregnation pretreatment, for example puncturing; Wood impregnation aids not directly involved in the impregnation process
  • B27K3/34—Organic impregnating agents
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
  • B27K—PROCESSES, APPARATUS OR SELECTION OF SUBSTANCES FOR IMPREGNATING, STAINING, DYEING, BLEACHING OF WOOD OR SIMILAR MATERIALS, OR TREATING OF WOOD OR SIMILAR MATERIALS WITH PERMEANT LIQUIDS, NOT OTHERWISE PROVIDED FOR; CHEMICAL OR PHYSICAL TREATMENT OF CORK, CANE, REED, STRAW OR SIMILAR MATERIALS
  • B27K3/00—Impregnating wood, e.g. impregnation pretreatment, for example puncturing; Wood impregnation aids not directly involved in the impregnation process
  • B27K3/52—Impregnating agents containing mixtures of inorganic and organic compounds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
  • B05D7/50—Multilayers
  • B05D7/56—Three layers or more
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/31504—Composite [nonstructural laminate]
  • Y10T428/31551—Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]

Definitions

• the present invention is directed to methods for reducing face checking of a wood product by coating at least a portion of the wood product with a composition comprising a (meth)acrylate moiety and a pigment, wherein the cured coating has a Tg of 35°C or less.
• Wood products are desired and used in a number of industries, such as furniture, flooring, millwork and cabinets. Wood products, such as those made from wood, veneers and wood composites, will often contain more than one substrate, and can comprise, for example, multiple plies.
• veneer for example, a thin piece of wood is applied over wood or wood composite products such as plywood or medium density fiberboard ("mdf").
• mdf medium density fiberboard
• the use of veneer and other wood composites is therefore often desired, as it gives the appearance of a solid wood without the cost.
• the thin layer of wood is subject to cracking or "checking", particularly upon exposure to hot and cold cycles. Cracks in the veneer can also occur because of humidity and the like; similarly, solid wood can crack due to exposure to environmental conditions.
• face checking Methods for reducing, if not eliminating, checking on the face of a wood product.
• US-A-2003/0050390 discloses radiation-hardening coating compositions for flooring materials made of wood that provide coatings having improved abrasion resistance.
• the compositions comprise a urethane acrylate monomer and a hydroxyfunctional ester.
• this document is silent about the glass transition temperature of the cured coatings obtained and does not treat the problem of face checking.
• the present invention is directed to a method for reducing face checking of a wood product comprising coating at least a portion of the wood product with a composition comprising a (meth)acrylate moiety and a pigment, and curing the coating by crosslinking, wherein the cured coatings, has a Tg of 35°C or less as determined by dynamic mechanical analysis of a free film having dimensions of 15 x 6.5 x 0.050 mm at an amplitude of 20 ⁇ m, a frequency of 1Hz and a heating rate of 3°C/min. Wood products having at least two ply, the outermost ply being wood, coated according to these methods are also within the scope of the present invention.
• the present invention is directed to methods for reducing face checking of a wood product comprising coating at least a portion of the wood product with a composition comprising a (meth)acrylate moiety and a pigment, wherein the coating, when cured, has a glass transition temperature ("Tg") of 35°C or less.
• wood product as used herein refers to any product comprising wood, and can include solid wood, hardwood, or products having at least two ply, the outermost ply being wood. Examples of such products include veneers, composites, and plywood.
• “Face checking” refers to the cracking or splitting that occurs at the surface of a wood product, which may or may not extend to varying depths below the surface of the wood product and/or which may rise above the surface with or without splitting.
• compositions used in the present methods comprise a (meth)acrylate moiety.
• (meth)acrylate moiety refers to any compound that has at least one (meth)acrylate functional group.
• Method(acrylate) refers both to methacrylate and acrylate. Any (meth)acrylate moiety can be used, provided it gives the desired flexibility to the coating composition. Examples include urethane (meth)acrylates, such as those commercially available from Bayer in their ROSKYDAL line of products (ROSKYDAL LS 2298), from Sartomer Company, Inc. (CN966J75, or CN 981), or from UCB Chemicals, Inc.
• the urethane (meth)acrylates can be aromatic or aliphatic.
• Other suitable (meth)acrylate moieties include (meth)acrylated epoxies, (meth)acrylated polyesters, (meth)acrylated amines, (meth)acrylated acrylics and/or mixtures thereof. Combinations of (meth)acrylate moieties can also be used.
• at least one (meth)acrylate moiety has a functionality greater than two and in certain embodiments at least two (meth)acrylate moieties are used, at least one of which has (meth)acrylate functionality greater than two.
• the coating composition further comprises a pigment (sometimes referred to as a "filler" in the formulation).
• Suitable pigments/fillers include, for example, silicas, inorganic oxides, calcium carbonates, aminosilicates, zinc oxide, titanium dioxide, and the like.
• the pigment may or may not impart opacity, depending on the needs of the user.
• the pigment is used in a relatively high weight percent; that is, the pigment ranges from 20 to 60 weight percent, with weight percent based on total solid weight of the composition. It was surprising that the coating compositions of these embodiments retained the flexibility desired to reduce, if not eliminate, face checking of a wood product; typically, highly loaded systems (i.e. systems with a weight percent in this range) are relatively inflexible. "Reduce” and like terms used in reference to cracking refer to reducing the size of the crack(s) and/or reducing the number of crack(s).
• the use of pigment/filler in the present compositions allows the desired viscosity to be achieved.
• the viscosity of the coating can be such that it can be pushed into or "filled” in the grain and/or pores of the wood.
• the viscosity of the coating can be for example 10,000 to 75,000 mPa ⁇ s [centipoises ("cPs")] such as 1 0,000 to 50,000 mPa ⁇ s (cPs), 20,000 to 50,000 mPa ⁇ s (cPs), 20,000 to 40,000 mPa ⁇ s (cPs), or about 30,000 mPa ⁇ s(cPs), +/-5,000 mPa ⁇ s (cPs), with viscosity measured with a Brookfield viscometer, for example a model RVT viscometer, with a No. 7 spindle at 50 RPM at 25°C. It will be appreciated that the viscosity of the coatings used in these embodiments is not as thick as, for example, a putty,
• the coatings of the present invention can further comprise one or more diluents.
• Suitable diluents include, for example, glycerol propoxy triacrylate, propoxylated neopentyl diacrylate, 1,6 hexanediol diacrylate, isodecyl (meth)acrylate, isobornyl (meth)acrylate, lauryl (meth)acrylate, 2-phenoxyethyl acrylate, ethylene glycol di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate, 1,4-butanediol diacrylate, 2,3-dimethylpropane 1,3-diacrylate, 1,6-hexanediol di(meth)acrylate, dipropylene glycol diacrylate, ethoxylated hexanediol di(meth)acrylate, propoxylated hexanediol di(meth)acrylate,
• the coating comprises a (meth)acrylate moiety having a (meth)acrylate functionality greater than two, and a diluent having a (meth)acrylate functionality less than two.
• the coatings used according to the present invention can further comprise various other additives standard in the art.
• suitable photoinitiators include, for example, benzyl, benzoin, benzoin methyl ether, benzoin isobutyl ether benzophenol, acetophenone, benzophenone, 4,4'-dichlorobenzophenone, 4,4'-bis(N,N'-dimethylamino)benzophenone, diethoxyacetophenone, fluorones, e.g., the H-Nu series of initiators available from Spectra Group Ltd., 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-isopropylthixantone, ⁇ -aminoalkylphen
• the coatings can be cured by any crosslinking mechanism, for example, thermally.
• Suitable thermoinitiators include peroxides and amines. When used, these other additives are typically present in the composition in an amount of up to 30 weight percent, with weight percent based on the total solid weight of the composition.
• the composition can be water-based, solvent-based, or 100 percent solids.
• the coating compositions can be prepared by any means known in the art.
• the liquid components can be added to a tank with agitation; powder can then be added, followed by any other desired additives. Agitation can be continued until the blend is substantially homogenous, and, in certain embodiments, until it has a Hegman grind of 2 to 7.
• the coatings can be applied to the wood product using any means standard in the art for a product having the desired viscosity such as pumping, pouring, and the like.
• a roll coat fill machine is a particularly suitable means of application.
• the coating is typically applied in an amount of 12.7 to 127 ⁇ m (0.5 to 5 mils), such as 25.4 to 50.8 ⁇ m (1 to 2 mils), wet film thickness.
• the wood product may be stained prior to treatment according to the present invention.
• a stain may be applied first and cured or dried.
• the coatings described herein can then be applied to the stained wood product, generally to fill the pores and give the finished product a smooth full-filled look; the present coatings can then be cured, sanded and/or have other coatings applied to the wood product, such as decorative and/or protective coats.
• the protective layers comprise layers for abrasion resistance, sanding sealers and/or topcoats.
• the present coatings can also be applied to a wood product not having stain and/or any other treatment, and/or can also be used with other coatings, layers, and/or treatments.
• the present invention is further directed to a wood product treated according to the present methods.
• the wood product treated according to the present invention can undergo 10 hot and cold cycles, such as up to 20 cycles, with little or no face checking.
• a wood product treated according to the present methods and having a treated "face” of 1.03 m 2 (40 square inches) +/- 161 cm 2 -(5 square inches) may have five or fewer cracks of 5.08 cm (2 inches) or less after ten hot and cold cycles.
• One "hot and cold cycle” refers to exposing the wood product to one hour at 49°C (120°F), one hour at -21°C (-5°F), and 15 minutes at room temperature.
• the coating used in the present invention has sufficient flexibility to expand and contract with wood upon exposure to various environmental conditions, such as humidity, heat, cold, and the like.
• the cured coating has a Tg of 35°C or less, with Tg determined as defined above.
• compositions used according to the present invention specifically exclude using a composition that comprises a hydrophilic polymer in conjunction with a reactive monomer.
• Other embodiments specifically exclude the use of an oligourethane acrylate with urea groups and/or a reactive polyester.
• the compositions used according to the present invention are not "stains" as that term is used in the art, which is used in a low viscosity form and is used typically to impart color to the wood product.
• a "flexible" filler according to the present invention was tested against two other commercially available fillers. All wood products tested were Southern Red Oak veneer, having applied thereto a stain, filler, high abrasion sealer, sanding sealer and topcoat. The wood product having a flexible filler according to the present invention and one of the other wood products having a commercially available "non-flexible” filler used coatings commercially available from PPG Industries, Inc.; other than the filler, all the coatings were the same for these two tested wood products. The third wood product was coated with products supplied by Chemcraft. Two boards for each system were tested, each board being approximately 1.03 m 2 ⁇ 161 cm 2 (40 in 2 +/-5 in 2 ).
• R1596Z-8 is commercially available from PPG Industries, Inc., and comprises a urethane acrylate and approximately 36 weight percent of filler.
• R1340Z-8 is commercially available from PPG Industries, Inc. and comprises an epoxy acrylate, a reactive polyester and approximately 25 weight percent of filler. This product is sold as a filler, and is not regarded as a "flexible" filler.

Landscapes

• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Wood Science & Technology (AREA)
• Chemical & Material Sciences (AREA)
• Forests & Forestry (AREA)
• Materials Engineering (AREA)
• Organic Chemistry (AREA)
• Inorganic Chemistry (AREA)
• Paints Or Removers (AREA)
• Chemical And Physical Treatments For Wood And The Like (AREA)
• Application Of Or Painting With Fluid Materials (AREA)
• Investigating Or Analysing Materials By The Use Of Chemical Reactions (AREA)
• Macromonomer-Based Addition Polymer (AREA)
• Investigating Or Analysing Materials By Optical Means (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (2)

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Family Applications (1)

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Families Citing this family (7)

Family Cites Families (13)

• 2004
  • 2004-12-17 US US11/016,581 patent/US7498061B2/en not_active Expired - Fee Related
• 2005
  • 2005-12-02 MY MYPI20055647A patent/MY148965A/en unknown
  • 2005-12-06 TW TW94142973A patent/TWI314091B/zh not_active IP Right Cessation
  • 2005-12-14 AR ARP050105233 patent/AR052813A1/es active IP Right Grant
  • 2005-12-16 CN CN200580046200XA patent/CN101098761B/zh active Active
  • 2005-12-16 CA CA 2591098 patent/CA2591098C/en not_active Expired - Fee Related
  • 2005-12-16 BR BRPI0517205-5A patent/BRPI0517205A/pt not_active IP Right Cessation
  • 2005-12-16 NZ NZ555802A patent/NZ555802A/en not_active IP Right Cessation
  • 2005-12-16 KR KR1020077016230A patent/KR101031387B1/ko not_active IP Right Cessation
  • 2005-12-16 ES ES05854652T patent/ES2389846T3/es active Active
  • 2005-12-16 AU AU2005316273A patent/AU2005316273B2/en not_active Ceased
  • 2005-12-16 EP EP20050854652 patent/EP1833618B1/en not_active Not-in-force
  • 2005-12-16 WO PCT/US2005/045979 patent/WO2006066222A1/en active Application Filing
  • 2005-12-16 PL PL05854652T patent/PL1833618T3/pl unknown
• 2007
  • 2007-07-17 NO NO20073694A patent/NO20073694L/no not_active Application Discontinuation
• 2008
  • 2008-06-18 HK HK08106730A patent/HK1116127A1/xx not_active IP Right Cessation

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